Brake linings and method of making the same



April 20, 1954 G. WALTERS ETAL. 2,676,126

BRAKE-LININGS AND METHODS OF MAKING THE SAME Filed Dec. 25, 1950 7 Sheets-Sheet l AMM/megs 7 Sheets-Sht 2 April 20, 1954 G.wA| 'rr-:Rs ErAl.

BRAKELININGS AND METHODS 0E MAKING THE sAME Filed Dec. 23. 1950 '7 Sheets-Sheet 3 G. wALTERs Er AL BRAKE-LININGS AND. METHODS OF MAKING THE SAME April 20, 1954- Fil-6d DSO. 25. 1950 April 20, 1954 l G. WALTERS ETAL BRAKE-LININGS AND METHODS OF MAKING THE SAME 7 Sheets-Sheet 4 Filed Dec. 25, 1950 April 20, 1954 G. wALTt-:Rs ETAL BRAKE-LININGS AND MEhTHoDs 0F MAxlNG THE SAME 7 Sheets-Sheet 5 Filed Dec. 25. 1950 m w my@ W fmMm. ,/W w Wmw/ n M @w April 20, 1954 G. WALTERS ETAL 2,676,125

BEAKE-LININGS AND METHODS 0E MAKING THE SAME Filed Deo. 23, 1950 7 Sheets-Sheet 6 20g 203 ZOO April 20, 1954 G, WALTERS ETAL 2,676,126

BRAKE-LININGS AND METHODS. OF MAKING THE SAME Filed Dec. 23, 195o 7 shets-sheet 7 Patented Apr. 20, 1954 NITED CFFICE BRAKE LININGS AND METHD OF MAKING THE SAME Application December 23, 1956, Serial N o. 292,461

(Cl. li-8l) claims. 1

This invention relates to improvements in brake-linings or brake friction-strips, and methods of making the same.

One object of this invention is to provide an improved brake-lining in which a large portion of the strength of the lining is provided by strands, and in Which a desirable Wide range of friction properties is feasibly obtained by employing separately-formed plastic material which permits of uniformly distributing heavy and/or coarse particles of friction-modifying agents through the lining.

Another object of this invention is to provide an improved method of making the herein described brake-lining.

Other objects and advantages will appear to those skilled in the art from the following, considered in conjunction with the accompanying drawings.

In the description and claims, the various parts and steps are identified by specic terms for convenience, but they are intended to be as generic in their application as the prior art will permit.

In the accompanying drawings forming part of the present disclosure, in which certain Ways of carrying out the invention are shown for illustrative purposes:

Fig. 1 is a face View of a brake-lining or brake friction-strip made in accordance With this invention;

Fig. 2 is a iront elevation of Fig. 1;

Fig. 3 is a face view of a portion of a Woven web used for making a brake friction-strip in accordance with this invention;

Fig. 4 is an enlarged transverse sectional view on line i-l of Fig. 3;

Fig. 5 is a face View of a modified form of web made by braiding instead of by Weaving;

6 is a View similar to Fig. 3 of the Woven web oi Fig. 3 after it has been impregnated with friction material;

Fig. 7 is a face view of a plastic member oi friction material which is to be combined with the impregnated web of Fig. 6 to produce a brake friction-strip in accordance with this invention;

Fig. 8 is a transverse sectional view on line of Fig. 7;

Fig. 9 is a top plan view illustrating the mode or. combining the impregnated web-member of Fig. 6 with the plastic member of Fig. 7 to form a composite member;

Fig. 10 is a front elevation of Fig. 9;

Fig. 11 is an enlarged sectional View on line ii--H of Fig. 10;

Fig. 12 is a sectional view similar to Fig. 11, o, .a modied construction;

Fig. 13 is a sectional View similar to Fig. 11 ci another modified construction;

Fig. 14 is a schematic side elevation partly in section, illustrating a method of forming the composite member illustrated in Figs..9, 10 and 1l:

Fig. 15 is a top plan View of a portion of Fig. 14;

Fig. 16 is a top plan view of the right-end portion of the construction shown in Fig. 14;

Fig. 17 is a sectional View on line ll--l'l of Fig. 14;

Fig. 18 is a sectional View on line I8-l8 of Fig. 14;

Fig. 19 is a sectional view on line lil-I9 of Fig. 14;

Fig. 20 is a sectional view on line 20-20 of Fig. 21 is a top plan view, partly in section,

illustrating a method of forming a plurality of composite members similar to the composite member illustrated in Figs. 9, 10 and 11, arranged in side-byside relation and upon their lower edges, into a brake-lining strip or member;

Fig. 22 is an edge elevation partly in longitudinal section oi Fig. 21;

Fig. 23 is a transverse sectional View on line 23-23 of Fig. 22;

Fig. 24 is a transverse sectional view on line Ztl-2t of Fig. 22;

Fig. 25 is a transverse sectional View on line 25-25 of Fig. 22;

Fig. 26 is a transverse sectional View illustrating the pressing operation employing hea and pressure; Y

Fig. 27 is a top plan View illustrating a single Wide web-member and a plurality of plastic members being formed into a single Wide composite member to be later formed into a brake-lining strip or member;

Fig. 28 is a front elevation of Fig. 27;

Fig. 29 is a sectional view on line 29-29 of Fig. 28;

Fig. 30 is a sectional view on line 30-30 of Fig. 28;

Fig. 31 is a sectional View on line 3I-3l of Fig. 28;

Fig. 32 is a schematic side elevation, partly in section, illustrating a method of forming the ccmposite member illustrated in Figs. 27 to 31;

Fig. 33 is a perspective View of the formingplate constituting part of the mechanism illustrated in Fig. 32;

Fig. 34 is a sectional View on line 34-34 of Fig. 32;

Fig. 35 is a sectional view on line 35-35 Vof Fig. 32;

Fig. 36 is a sectional View on line 35-55 of Fig. 32;

Fig. 37 is a sectional View on line 5?-37 of Fig. 32;

Fig. 38 is a sectional view on an enlarged scale of a modified form of the composite member illustrated in Fig. 31;

Fig. 39 is a View on an enlarged scale, of a View similar to Fig. 31 of another modied form of composite member;

Fig. 40 is a view similar to Fig. 39 of another modied form of composite member;

Fig. 41 is a sectional view on line dl-iii of Fig. 42, of another modified form of composite member;

Fig. 42 is a schematic side elevation, partly in section, illustrating a method of making the form of the composite member illustrated in Fig. 41,'

Fig. 43 is a sectional view on line 45-45 of Fig. 44 illustrating another modified form oi composite member;

Fig. 44 is a schematic side elevation illustrating a method of making the form of the composite member illustrated in Fig. 43;

Fig. 45 is a View similar to Fig. 39 illustrating another modified form of composite member;

Fig. 46 is a View similar to Fig. 40 illustrating another modified form of composite member;

Fig. 47 is a View corresponding to Fig. 23, of a modified construction of brake-lining illustrated in Figs. 47 to 50, but with the forming-tube omitted;

Fig. 48 is a view corresponding to Fig. 26, with the dies omitted and the flash removed, of the modified construction illustrated in Figs. 47 to 50;

Fig. 49 is a top plan view of the reticular woven bottom member Vshown as forming the bottom portion of the brake-lining of Figs. 47, 48 and 5i); and

Fig. 50 is an edge elevation similar to Fig. 2, of the modified form of brake-lining illustrated in Figs. 47 to 50.

Referring to Figs. 1 to 4, 6I to l1, and 2l to 26, showing the particular form of the invention chosen for illustration therein, the brake-lining or friction-strip 55 is made as will presently be set forth. A web is made by loosely weaving an open readily impregnated web or web-member l of warp strands 52 and a weft strand or weft picks 53" as illustrated in Figs. 3 and 4. The web 5l is then passed into or through a tank, not shown, containing heat-hardenable plastic bonding friction material 54 to form the impregnated or treated web 55 shown in Fig. 6. No particular bonding friction material is any part of the present invention, and any suitable bonding friction material may be used, such, for example, as bonding friction material containing a phenol-formaldehyde type of resin, as is well known to those skilled in the art. The bonding material initially is in the form of a heavy liquid solution which impregnates and clings to the web, which is then dried.

Also, a heat-hardenable bonding friction material plastic member 5B is molded in any suitable Way, of the desired ingredients, as for example, by extruding it through a die. A suitable length of the plastic member 55 is then combined with a suitable Corresponding length of the impregnated or treated web 55 in any suitable way as, for example, by successively folding the sideportions of the web 55 about the plastic member 55 by hand or otherwise, to produce a composite member 51 which, throughout its length, is as illustrated in the right-hand end-portions of Figs.

9 and 10, and in the cross-sectional view of Fig. 11. Although the impregnated web-member 55 has been dried before it is combined with the plastic member 55 to form the composite member 5l, nevertheless the dried impregnated Webmember 55 is pressure-adhesive while cold, so that in addition to the strands of the web-member 55 being readily pressable into the surface of the plastic member 55 as will appear from Fig. 1l, the two side edge-portions 58 and 55 are readily pressable by hand or otherwise into adhesive engagement with one another along the location 60, to thus aid in maintaining the members 55 and 55 of the composite member 5l in assembled relation during distortion of the same in performing later steps or operations.

Instead of forming the composite member 5l by hand, it can be formed by means of the mechanism illustrated in Figs'. 14 to 20 inclusive. Referring to Fig. 14, a reel 6| containing a reeled-up length of impregnated web 55, has its trunnions 52 removably mounted for rotation in supportingarms 63.

An extrusion mechanism 64 includes a cylindrical pressing-chamber 65 provided with a throat-entrance '55, through which chunks of plastic material 5l are received from a hopper E5. The pressing-chamber 65 has an extrusion-screw 55 fitting therein, which screw, by rotating, forces the plastic material out through the extrusionhole lil in the extrusion-die 'l l.

The impregna-ted web 55 is drawn up over the guide-pulley 'l2 and passes into the ilared throat 'I3 merging into the generally cylindrical passage through a forming-guide it, which curls the impregnated web up into a generally hollow form around the extruded cylindrical plastic member 5B which comes through the die-opening l5 and through the generally cylindrical guide-passage of a guide l5, and on into the hollow-shaped portion of the impregnated web 55 which is being folded around it and pressed into it, more or less, and then passes between a pair of feeding and pressing-rollers 'i6 and TI, respectively, mounted on shafts 'I8 and 19 which are driven at equal speeds by the shaft 'i9 and spur gears 85 and 8i. The shaft l5 may be driven by adjustable mechanism in a way well understood by those skilled in the art, to permit of driving the feed-rolls l5 and Tl at any desired speed to feed the extruded plastic member 56 at the same speed that it is extruded through the die ll. As the plastic member 56 and web-member 55 pass through the forming-guide 14, a holding-linger l-a at the front portion of guide 'i4 extends dov/n between the edge-portions 58 and 59 of the web-member, and holds the plastic member 55 down below the edges of the edge-portions 58 and 55. And as the plastic and web-members pass out of the rear end of guide i4, the smooth under face of a rear extension '14h thereof holds the top edges of the web 55 at equal heights, and the smooth blunt-pointed rear portion 14o of member lllb holds open, or spreads open if necessary, the edge-portions of the Web-member 55, and holds the plastic member 56 down in proper position, so that the edge-portions 58 and 59 of the webmember 55 stand up and apart preparatory to their being engaged by the pressing-rollers 'l5 and il. Each of the rollers 'i6 and 'll has a generally semicircular annular groove 82, which groove, as shown in Fig. 20, gives a generally cylindrical form to the composite member 5l, while the cylindrical surfaces 53 on the rollers 76 and 'Il press the .two edge-portions 58 vand 59 together to adhere them together along the location 60 (Figs. 20 and 11).

In order to cut the composite member off into suitable predetermined lengths while it continues to travel and be formed from the previouslyformed and dried web 55 and the extruded plastic member 58 as the latter is being made by the extrusion-die, suitable mechanism is provided as will now be described.

A horizontal shaft 84 is rotatably mounted in bearing-supports 85 and 88 and has firmly secured to it by set-screws or otherwise, two troughsections 81 and 88. And in order to properly support the trough-section 88, the shaft 84 has a rearward shaft-extension portion 89 beyond the bearing-support 86. Both trough-sections are the same in cross section, and each trough-section 81, 88 has four troughs 90, 9|, 92 and 93, with four corresponding separating-partitions 84, 95, 98 and 91. Each of the partitions of the troughsection 88 has its end-portion adjacent the bearing-support 86 cut back from its outer edge to a location 98 sufficient to clear the four ratchetpins 90, |00, and |02, which extend through an end-plate |03 on the end of the trough-section 88 and into the partitions, for a purpose to be later described.

The bearing-supports 85 and 86 respectively have extensions |84 and |05 in which are rigidly secured a switch-support rod |06. A microswitch |01 is slidable along the support-rod |06 and securable in any desired adjusted position by collars |08 and set-screws |08, orotherwise. A switch-support arm ||0 is pivoted to swing on the switch-support rod |05 in a plane at right angles to the support-rod |06 and carries a switch-actuating arm adapted to close the micro-switch |01 to close the electrical circuit leading from a power supply ||3 when the end of the composite member 51 pushes the actuating-arm A cutter ||4 is rotatably mounted at ||5 on a support H8 and has four cutting-blades ||1, ||8, l i3 and |20. The cutter |4 also has four ratchetpins |2I, |22, |23 and |24. A solenoid-coil |25, when electric current flows through it, draws the solenoid-armature |26 down into the coil |25 and pulls the pawl-arm |21, which is pivoted at |28 on the solenoid-armature, to thus cause pawlhead |28 to p-ull down on the ratchet-pin |2|, to thereby cause the cutter-blade ||4 to sever the composite member 51, which is constantly traveling through the opening |30 in the support-plate lis. This downward swinging movement of the ratchet-pin |2| continues until it occupies the position shown by the ratchet-pin |22 in Fig. 19. spring-pressed buffer-pins |3| engage the upper face of the frame |32 to minimize the shock at the end of the downward movement of the pawlarm |21. The downward movement of the pawlarm |21 takes place against the counter-action of the spring |33 which pulls the pawl-arm back up to its original position, as shown in Fig. 19, as soon as the electric current through the solenoidcoil |25 ceases. The leaf-spring lock |34 is secured to the support ||8 so that it prevents reverse movement of the cutter ||4 by engaging the rear of each cutter-blade after such cutterblade has been forced past it by the pawl action previously described. The solenoid-armature |26 carries a switch-closing arm |35 which closes the switch |33 when the armature |25 is pulled to its lowered position by the solenoid-coil |25.

A second solenoid-coil |31 is adapted, when supplied with electric current, to pull its solenoidarmature |38 downward and carry along with it the pawl-arm |39 which is pivoted to the armalture at |40. The pawl-arm |38 carries springpressed buier-pins |4| which engage against the frame |32 to minimize the shock at the end of the down movement of the pawl-arm |38. When kthe pawl-arm |30 thus moves downward, its pawlhead |42 pulls the ratchet-pin 90 downwardly to the position occupied by pin |00 in Fig. 18. Upon the electric current being shut off from the solenoid-coil |31, the coil-spring |43 returns the pawl-arm |38 upwardly to its original position shown in Fig. 18, ready for the next downward movement. A leaf-spring lock 22| secured to the support 83 prevents reverse movement of the trough-sections 81, 88 by engaging the rear of each trough-partition after such trough-partition has been forced past it by the pawl action previously described.

When the previously-referred-to engagement or the end of the composite member 51 against the switch-actuating arm takes place, the latter will close the micro-switch |01, to thus close the electric circuit therethrough, whereupon electric current flows through the wires |44 and |45 to the first-described solenoid-coil |25, to cause it to actuate the cutter ||4 to sever a length of composite member 51, which is of predetermined length by the particular setting oi the micro-switch |01 along the support-bar |00. When this cutting action takes place, the downward movement of the armature |26 causes the closing cf the switch |38 as previously described, to thus close the electric circuit through the wires |48 and |41 to cause the second solenoid-coil |31 to pull its armature |38 down, to thus cause the pawl-head |02 to pull one of the four ratchetpins 83, |00, |0| and |02 downwardly to cause the aligned trough-sections 81 and 88 to be rotated one-quarter of a turn, to thus dump the length of composite member 57 which has been cut, and bring the next-following trough into the position which was previously occupied by the trough which has just been described as having been dumped.

When the trough-sections are rotated oneduarter turn as just described, this causes the switch-supporting arm ||0 to be swung about its pivot until the trough-partition which engages the switch-supporting arm H0, pushes past it, whereupon the weight of the switch-arm swings the latter down to its original position with the switch-actuating arm in position to close the micro-switch when the constantly-traveling next section of the composite member 51 pushes against the switch-actuating arm whereupon the cutting and dumping action previously described is, again repeated, and so on as long as the composite member continues to be fed along a trough to the location of the microswitch. To ensure that the switch-supporting arm ||0 returns to itsoperating position after a one-quarter rotation of the trough-sections, a leaf-spring ||2 or other resilient means may be provided.

In order to make brake-lining out of the composite member 51 as hereinbefore set forth, a suitable number of dried composite members 51 are passed in eide-by-side contact relation with one another through a tapered forming-tube |48 v(Figs. 2l and 22) of generally rectangular internal cross-sectional form, which presses the members 51 sidewise together and closes up the spaces between them and somewhat compresses the members 51 down edgewise (Figs. 22 and 24) 7 whereupon the pressed-together members 51 pass between a `pair of rolls |49 and |50, the roll |50 of which has a pair of :flanges il spaced apart the same distance as the width of the pressedtogether i embers 51 as they leave the formingtube |43. The rolls |49 and |50 press the members 51 down edgewise to a relatively-:1eme coherent mass forming a strip |52 of the general form illustrated in Fig. 25. The compressed coherent strip |52 is then cut into suitable lengths, each of which is subjected to heat and pressure between die-members |53 and |511 (Fig. 26) to density and semi-cure the strip |52 intoa partly heat-hardened unitary dense member or mass l having hash-portions |55, which nashportions are subsequently trimmed off, whereupon the trimmed members |55 are heated and bent to and hel-:i in their final curved forms, such as illustrated in Fig. 2, whereupon they are given the necessary additional heat treatment to completely cure them to nal condition, after which they are ground to the finished form illustrated in Figs. 1 and 2. If the braise-lining is to be secured to a brake-shoe by cementing, rivet-holes are not needed, otherwise the lining would be provided with the usual rivet-holes. The arcuate friction or braking-ace portion |51 of the brakelining member (Fig. 2), provides an arcuate braking-face |56 throughout the wear-life of the lining, and the baci; portion his provides the back face 222 which, of course, is not subject to any wear.

Instead of employing a web in which the strands are interlaced by weaving as heretofore described, a web having otherwise interlaced strands as, for example, the braided web 'ite shown in Fig. 5 may be made by braiding the strands lei. Before use,l the braided web it@ would be impregnated with plastic friction mateu rial, the same as in the case of the woven web 5| of Fig. 3. The strands employed in the various formsV of the present invention preferably are the usual'asbestos strands provided with a corestrand or strands of brass, zinc or other suitable metal.

Instead of making the composite member 51 as illustrated in Figs. 9 to 11, a composite member 223 as illustrated in Fig. 12 could be employed, in which the plastic core-member |52 was originally of an approximate rectangular r shape instead of the cylindrical shape of Figs. 9 to 11. Or, a composite member |63 as illustratedin Fig. 13 could be employed, in which the plastic core-member It could be cylindrical as in the case of the plastic member of Fig. 11, but of larger size than the plastic member of Fig. 11 as compared to the width of the web-member, so that the two edges |55 and 16S of the webmember are spaced apart somewhat, as shown in Fig. 13.

While it is advantageous to manufacture the composite member by a ycontinuous process as hereinbefore set forth, it will be appreciated that composite members for making brake-lining in accordance with this invention can be made by hand, and even without making the plastic core-member by extruding it. Thus, the coremember, which does not have to be perfectly round or of any particular contour for use in this process, can be made by shaping a plastic mass up into a general rod-like shape by the hands. And then the previously-woven or braided member can be placed about the coremember and pressed thereinto by hand, also. And the thus handmade composite member can 8 be made in any predetermined length desired, or can be made -in 'a long length and cut by hand-operatedY means or otherwise into the desired length, which can be made into brakelining in accordance with this invention.

By having the plastic members as hereinbefore set'forth, it is possible to have coarse heavy particles such, for example, as brass chips, and also other heavy modifying agents such as particles of lead or other metals or barytes, and so forth, which cannot be satisfactorily maintained properly and uniformly mixed even in a thick liquid such as is employed in passing the webmember through for impregnation. And yet these heavy components, Vwhich are very desirable to have present in friction-disks, can be very uniformly distributed through the finished friction-disks, and economically made by the methods hereinbefore set forth, since they will be uniformly distributed throughout the plastic member and yet, when the heat and pressure is applied, the material of the plastic members flows through and between the openings or interstices of the woven or braided members so that the nal result is a satisfactorily uniform brake-lining construction.

Instead of employing a composite member of relatively-small volume which requires a number of them to be arranged in side-by-side relation to produce a brake-lining as hereinbefore set forth, the single composite member l, as illustrated in Fig. 27, can be made from a relatively-wide impregnated web-member |68 combined with a plurality of plastic members it@ to produce the composite member |61. In producing the composite member |61, the Webmember and the plastic members are brought into relation with one another as illustrated at the left end of Figs. 27 and 28 and compressed widthwise and thicknesswise as they pass along through mechanism shown in Figs. 32 to 36, so that the composite member changes from the form illustrated at the left of Figs. 27 and 28 and shown in the cross-sectional View of Fig. 29, to the form shown in Fig. 30 and then to the form shown` in Fig. 31 and, finally, to the heavily compressed or rolled form shown in Fig. 37, which corresponds to the friction-strip |52 shown in Fig. 25 for the form of the invention illus*1 trated in Figs. 21 to 25.

Thus, referring to Figs. 32 to 37, the wide web member |68 is of a width to extend down the side slot-portions |16) and 11| of the forming-plate |12, and is passed along over the upper curved surface |13 of the forming-plate i12 in orderV to provide a loose quantity of material that can be folded down into the multi-rib shape to take the plurality ofV plastic members lst within the upper folds |14 of the web-member |68 wi'thout'producing an undue degree of side dragv on the side edge-portions of the web-mem ber in this folding or rib-forming operation on the web-member. This folding action is brought about by having a plurality of lower foldingngers |15 on the forming-plate |12, and by having an upper forming-plate |16l provided with a plurality of downwardly-extending lingers |11 which. act in cooperation with the lower lingers |15. After the web-member |8 passes beyond the fingers of the forming-plates |12 and |16, the plastic members |69 are brought into the top folds of the web-member as shown in Fig. 29, and then as the web-member and plastic members pass into and through the shaping-tube |18,the side edge-portions |19 and |88 of the web-member |68 are folded up against the sides of the two outside plastic members |69, and the top portions of the upwardly-extending loops |8| are somewhat flattened down, all as shown in Fig. 30, and then as the web and plastic members pass through the end of the shaping-tube |18, the web-member is further compressed and shaped down to the form generally indicated in Fig. 3l. And then as the composite member |61 illustrated in Fig. 31 passes through the two rolls |82 and |83, the composite member |51 is squeezed down to the highlycompressed form |84 shown in Fig. 37, which corresponds to the member |52 shown in Fig. 25. The further processing of the member |84 shown in Fig. 37, to a. completed brake-lining member, can be the same as was described as concerned the pressed member |52 shown in Fig. 25.

Instead of employing a composite member such as |67 illustrated in Fig. 31 to press down into a dense mass or strip |82 as shown in Fig. 37 for later processing into a finished brake-lining, a composite member |85 which would be substantially thinner and wider than .the composite member |67 of Fig. 31, could be rolled up as shown in Fig. 38 and then formed by pressurerolls or otherwise into a dense pressed strip similar to the strip |84 of Fig. 37 for later processing into a brake-lining.

Another form of composite member could be the composite member |86 illustrated in Fig. 39 which originally would be a strip thinner and Wider than the composite member |61 of Fig. 3l, and which would be folded at its locations |81 and |33 to swing the fold-portions |69 and |92 upwardly and inwardly to bring their edges adjacent one another at the location |9|, and would then be formed into brake-lining in the manner hereinbefore described.

Another form of composite member |92 is shown in Fig. 40 which is made suitably thin and wide so that when folded at its center portion |93 to produce two layers as illustrated, it provides suitable volume and proportions of webmember and plastic members to be formed into f a brake-lining similar to the way hereinbefore set forth.

Another form of composite member |94 shown in Fig. 41 looks very similar to the composite member |61 shown in Fig. 31, the main diiference being that the three plastic members |95 are located in upper opening folds of the web-member |955, while the other two plastic members |91 are located in lower opening folds of the webmember ie'. This can be accomplished as illustrated in Fig. 42 by bringing the upper group of plastic members |95 downwardly toward and into the upper folds of the web-member |96, while at the same time the lower plastic members |91 are brought upwardly to the lower folds thereof, the entire procedure being accomplished in a manner that will be readily understood by those skilled in the art in the light of the herein disclosed methods of producing other forms of the invention.

In the modified form of composite member |98 shown in Fig. 43, two separate web-members |92 and 229 are employed and are so folded that the upper web-member |99 provides three upper folds in which are located the three plastic members 23|, while three plastic members 282 are located in three lower opening folds in the lower webmember 228, and four other plastic members 283 are located in what amounts to equivalents oi folds which are formed as a result .of the two upper and lower web-members |99 and 200 being located adjacent one another. In making this form of composite member |88, it will be accomplished as illustrated in Fig. 44 by having the three sets of plastic members 20|, 282 and 203 brought into the folds of the folded web-members |99 and 20d, as illustrated in Fig. 44.

Another way of making a large single composite member is the making of the composite member 22d illustrated in Fig. 45, by employing a single large rectangular plastic member 205 together with a wide web-member 206 which has its opposite side edge-portions 201 and 288 folded up and over toward and adjacent one another at the location 202.

Still another way of making a single large composite member is the composite member 2 illustrated in Fig. 46, which is formed by a relativelywide web-member 2| upon which is laid or into which is partly pressed a wide plastic member 2|2, after which the web and plastic member is folded up at the middle along the fold region 2 I3 to bring the left-end portion 2|4 up on top to its position as illustrated.

Instead of having one or more composite webmembers form the entire brake-lining strip or member, a brake-lining member 2|5 (Fig. 48) can be formed by employing a braking-face portion 2|6 formed of one or more composite members, as hereinbefore set forth, and by employing a reticular backing-member 2 to form the backface portion 2 |8. The reticular backing-member 2|1 may be made by weaving longitudinal warp strands 2|9with a transverse or weft strand or weft picks 228, the strands 2|9 and 220 will preferably be of wire-cored asbestos, or of bare wire or of other suitable material. Or the reticular member 2 can be any reticular member having sufficient mechanical strength to prevent possible splitting of the lining by the rivets commonly employed to secure a brake-lining member on a brake-shoe. Fig. 47 corresponds to Fig. 23 of the previously-described form of the inventionz with the forming-tube omitted and with the addition of the reticular backing-member 2|? at the back thereof. The brake-lining 2|5 of Fig. 48 corresponds to the similar member illustrated in Fig. 26, but with the dies omitted and the flash removed. Fig. 50 illustrates a side edge view similar to Fig. 2, of the brake-lining member 2|5 having the reticular reinforcing-member 2|'| forming the back-face portion 2l8 thereof. Where a back-face reinforcing-member 2|1 is employed, it will be made of a thickness in the iinal brake-lining which will never be reached by a brake-shoe during the wear-life of the brakelining, so that all the braking action throughout the wear-life of the brake-lining will take place against a portion of the brake-face portion 2| 6 formed of the composite members, which will ordinarily occupy more than half the thicknessl of the finished brake-lining. l

vBy forming a brake-lining or brake frictionstrip of one or more composite members, each of which is formed from one or more plastic members and one or more impregnated webmembers, the plastic members being formed separately or independently of the web-members, a number of important advantages are obtained. Thus, great economy of manufacture results. Also, a higher percentage of plastic material can be embodied in, and substantially uniformly distributed through, a brake-lining, than Where only one or more impregnated web-members are employed, since only a much smaller percentage of plastic material can be made to adhere to the web by the impregnating treatment. Also, coarse heavy particles such, for example, as brass chips, and also other desirable heavy frictionmodifying agents such as particles of lead and other metals and barytes, and so forth, can be easily embodied in a plastic member, although they cannot be easily maintained uniformly mixed ina liquid, even in a thiol; liquid such as is employed for impregnating web-members. When heat and pressure is applied to the composite members forming the rough friction-strip, the material of the plastic members is forced to flow between the strands and through the openings or interstices of the open web-members, so that the final result is a satisfactorily uniform brakelining construction. The invention may be carried out in other specific Waysthan those herein set forth without departing` from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming Within the meaning and equivalency range of the appended claims are intended to be embraced therein.

We claim:

1. A brake friction-strip having an arcuate braking-face portion, Yand comprising: one or moreV elongated heat-hardenabie composite members extendingr longitudinally oi Jfhe strip as a compressed heat-hardened unitary mass, and forming theY arcuate braking-face portion of the strip; each said composite member comprising an elongated separately-formed heathardenable bonding friction-material plastic member, and an elongated separately-formed heat-hardenable bonding friction-material-impregnated web-member, the web of Ywhich is mainly formed of strands, the separately-formed plastic member and the separately-formed vveb member of a composite member having been brought into close relation With one. another substantially throughout their length to form the composite member.

2. A brake friction-strip having an varcuate braking-face portion, and comprising: one or more. elongated heat-hardenable composite members extending longitudinally of the strip as a compressed heat-hardened unitary mass, and forming the arcuateV braking-face'portion of thestrip; each said composite member comprising an elongated separately-formed heathardenable bonding friction-material plastic member, and an elongated separately-formed heat-hardenable bonding friction-material-impregnated web-member, the web of Which is mainly formed of interlaced strands, the sep'- arately-formed plastic member and` the separately-formed Web-member of a composite member having been brought into close relation with one another substantially throughout their length to form. the composite member.

-3..A. brake friction-strip having an arcuate braking-face portion, and comprising: oneY or more elongated heat-hardenable composite'members extending longitudinally-of the strip as a compressed heat-hardened unitary mass, and forming-the arcuate braking-face portion of the strip; each said composite member comprising an elongated sepa-rateiyiormed heat-hardenable. bondingr friction-material plastic member, and an elongated separately-formed heathardenable bonding friction#material-impregnated Web--l memben the. web ofrwhich is mainly formed of.

Y bonding l2 interlacedV strands; and the web-member of a composite member having been Vfolded about the plastic member substantially throughout their length to form the composite.` member.

4. A brake friction-strip: having an arcuate braking-face portion, and comprising: a plurality of elongated heat-hardenable composite members extending longitudinallyof the strip and in side-by-side relation with one another as a compressed heat-hardened unitary mass, and forming the arcuate braking-face portion of the strip; each said compositev member comprising an elongated separately-formed heat-hardenable bonding friction-material plastic member, and an elongated separately-formed heat-hardenable bonding friction-material-impregnated Webmember, the web ofr which is mainly formed of strands, thev plastic member and the Web-member of a composite member having been brought into close relation With one another substantially throughout their length to form the composite member.

5. A brake friction-strip having an arcuate braking-face portion, and comprising: a Aplurality of elongated heat-hardenable composite members extending longitudinally of the strip and in side-by-side relation with one another as a. compressed heat-hardened unitary mass, and forming the arcuate braking-face portionA of the strip; each said composite member comprising an elongated separately-formed heat-hardenable bonding friction-material plastic member, and an elongated separately-formed heat-hardenable bonding friction-material-impregnated Webmember, the web of Vwhich isA mainly formed of interlaced strands, the separately-formed plastic member and the separately-formed Web-member of a composite member having been brought into close relation with one another substantially throughout their length to form the composite member.

6. A brake friction-strip having an arcuate braking-faceportion, and comprising: a plurality of elongated heat-hardenable composite mem bers extending longitudinally o the strip and in side-by-side relation with one another as a compressed heat-hardened unitary mass, and forming the arcuate braking-face portion of the strip; each said composite member comprising an elongated separately-formed heat-hardenable bonding friction-material plastic member, and an elongated separately-formed heat-hardenable friction-material-impregnated web member, the web of which is mainly formed of interlaced strands, and the web-member of a composite member having been folded about the plastic member substantially throughout their length to form the composite member.

7. A brake friction-strip having an arcuate braking-face-portion, and comprising: a plurality of elongated heat-hardenable composite members extending longitudinally ofV the strip and in side-by-side relation. with one another as a compressed heat-hardened unitary mass, and formingY the arcuate braking-face portionY of the strip; each saidV composite-member comprising an elongated separately-formedv heat-hardenable bonding friction-material' plastic member, and an elongated separately-formed heat-hardenable bonding.friction-materialimpregnated open webmember,l the web of which isv mainly formed of Y interlaced strands, and the Web-member of a composite member' having been folded about the plastic member substantiallyl tlircmg-houtV their Y length to form the` composite member.

8. The method of making a brake friction-strip having an arcuate braking-face, comprising: providing one or more elongated heat-hardenable bonding friction-material plastic members; providing one or more elongated heat-hardenable bonding friction-material-impregnated webmembers separately from the plastic members, the web of which is mainly formed of strands; bringing said plastic members and said Webnembers into close relation with one another substantially throughout their length to form one or more composite members each comprising a said plastic member and a said Web-member by causing successive portions of said plastic members to move relatively toward and into close relation With successive pre-made portions of said web-members; arranging one or mor composite members longitudinally to form the braking-face portion of the strip; and subjecting said arranged composite members to heat and pressure and orming a unitary brake frictionstrip having an arcuate braking-face portion.

9. The method of making a brake friction-strip having an arcuate braking-face, comprising: providing one or more elongated heat-hardenable bonding friction-material plastic members; providing one or more elongated heat-hardenable bonding friction-material-impregnated Webmembers separately from the plastic members, the web of which is mainly formed of interlaced. strands; bringing said plastic members and said web-members into close relation Iwith one another substantially throughout their length to form one or more composite members each comprising a said plastic member and a said Web-member by causing successive portions of said plastic members to move relatively toward and into close relation with successive pre-made portions oi said Web-members; arranging one or more composite members longitudinally to form the braking-face portion of the strip; and subjecting said arranged composite members to heat and pressure and forming a unitary brake friction-strip having an arcuate braking-face portion.

l0. The method of making a brake frictionstrip having an arcuate braking-face, comprising: providing one or more elongated heat-hardenable bonding friction-material plastic members; providing one or more elongated heat-hardenable bonding Web-members separately from the plastic members, the web of which is mainly formed of interlaced strands; folding each web-member of a composite member about a plastic member substantially throughout their length to form one or more composite members each comprising a said plastic member and a said Web-member by causing successive portions of said plastic members to move relatively toward and into close relation with successive pre-made portions of said web-members; arranging one or more composite members longitudinally to form the braking-face portion of the strip; and subjecting said arranged composite members to heat and pressure and forming a unitary brake friction-strip having an arcuate braking-face portion.

ll. IThe method of making a brake frictionstrip having an arcuate braking-face, comprising: providing one or more elongated heat-hardenable bonding friction-material plastic members; providing one or more elongated heathardenable bonding friction-material-impreg nated open web-members separately from the plastic members, the web oi which is mainly formed of interlaced strands; folding each webfriction-material-impregnated r 14,1' member of a composite member about a plastic member substantially throughout their length to form one or more composite members each comprising a said plastic member and a said Webmember by causing successive portions of said plastic members to move relatively toward and into close relation with successive pre-made portions of said web-members; arranging one or more composite members longitudinally to form the braking-face portion of the strip; and subjecting said arranged composite members to heat and pressure and forming a unitary brake friction-strip having an arcuate braking-face portion.

12. The method of making a brake frictionstrip having an arcuate braking-face, comprising: causing one or more elongated heat-hardenable bonding friction-material plastic members to travel longitudinally; causing one or more elongated heat-hardenable bonding frictionmaterial-impregnated Web-members, the web of which is mainly formed of strands, to travel longitudinally; bringing said traveling plastic members and web-members into close relation with one another substantially throughout their length to form one or more traveling composite members each comprising a said plastic member and a said web-member; cutting oif predetermined lengths of said composite members; arranging the composite members longitudinally to form said braking-face portions; and subjecting said arranged composite members to heat and pressure and forming unitary brake frictionstrips each having an arcuate `braking-face portion.

13. The method of making a brake frictionstrip having an arcuate braking-face, comprising: causing one or more elongated heat-hardenable bonding friction-material plastic members to travel longitudinally; causing one or more elongated heat-hardenable bonding frictionmaterial-impregnated Web-members, the web of which is mainly formed of interlaced strands, to travel longitudinally; bringing said traveling plastic members and Web-members into close relation with one another substantially throughout their length to form one or more traveling composite members each comprising a said plastic member and a said web-member; cutting off predetermined lengths of said composite members; arranging the composite members longitudinally to form said braking-face portions; and subjecting said arranged composite members to heat and pressure and forming unitary brake frictionstrips each having an arcuate braking-face portion.

14. The method of making a brake frictionstrip having an arcuate braking-face, comprising: causing one or more elongated heat-hardenable bonding friction-material plastic members to travel longitudinally; causing one or more elongated heat-hardenable bonding frictionmaterial-impregnated Web-members, the web of which is mainly formed of interlaced strands, to travel longitudinally; folding each web-member of a composite member about a plastic member substantially throughout their length to form one or more traveling composite members each comprising a said plastic member and a said webmember; cutting oi predetermined lengths of said composite members; arranging the composite members longitudinally to form said braking-face portions; and subjecting said arranged composite members to heat and pressure and 15v forming brake. friction-strips each having an arcuate braking-face portion.

15. The method of making, a |brake frictionstrip. havingl an arcuate braking-face, comprising: causing one or morel elongated heat-hardenable bonding friction-material plastic members to travel longitudinally; causing one or more elongated heat-hardenable bonding frictionmaterial-impregnated open Web-members, the web of which is mainly formed of interlaced strands, to travel longitudinally; folding each Web-member of a composite member about a plasticv member substantially throughout their length to form one or more traveling composite members each comprising a said plastic member 15 and a. said Web-member; cutting off predetermined lengths oi said composite members; arranging the composite` membersY longitudinally 1&- to form. said braking-face portions; and subieot ing said arranged composite members to heat and pressure. and. forming unitary brake frictionu strips each having anv arcuate braking-iace por tion.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 10 1,844,461 Chase Feb. e, ieee 1,875,645 Norton Sept. 6, 1932 2,025,039 Cannon Dec. 24, 1935 2,196,569 Stroehla etal. Apr. 9, 1946 2,553,698 Brahs May 22, 1951 2,555,261 Walters May 29, 1951 2,584,825 Walters et al. Feb. 5, i952 

1. A BRAKE FRICTION-STRIP HAVING AN ARCUATE BRAKING-FACE PORTION, AND COMPRISING: ONE OR MORE ELONGATED HEAT-HARDENABLE COMPOSITE MEMBERS EXTENDING LONGITUDINALLY OF THE STRIP AS A COMPRESSED HEAT-HARDENED UNITARY MASS, AND FORMING THE ARCUATE BRAKING-FACE PORTION OF THE STRIP; EACH SAID COMPOSITE MEMBER COMPRISING AN ELONGATED SEPARATELY-FORMED HEATHARDENABLE BONDING FRICTION-MATERIAL PLASTIC MEMBER, AND AN ELONGATE SEPARETELY-FORMED HEAT-HARDENABLE BONDING FRICTION-MATEREIAL-IMPREGNATED WEB-MEMBER, THE WEB OF WHICH IS MAINLY FORMED OF STRANDS, THE SEPARATELY-FORMED PLASTIC MEMBER AND THE SEPARATELY-FORMED WEBMEMBER OF A COMPOSITE MEMBER HAVING BEEN BROUGHT INTO CLOSE RELATION WITH ONE ANOTHER SUBSTANTIALLY THROUGHOUT THEIR LENGTH TO FORM THE COMPOSITE MEMBER.
 8. THE METHOD OF MAKING A BRAKE FRICTION-STRIP HAVING AN ARCUATE BRAKING-FACE, COMPRISING: PROVIDING ONE OR MORE ELONGATED HEAT-HARDENABLE BONDING FRICTION-MATERIAL-IMPREGNATED WEBVIDING ONE OR MORE ELONGATED HEAT-HARDENABLE BONDING FRICTION-MATERIAL-IMPREGNATED WEBMEMBERS SEPARATELY FROM THE PLASTIC OF STRANDS; THE WEB OF WHICH IS MAINLY FORMED OF STRANDS; BRINGING SAID PLASTIC MEMBERS AND SAID WEBMEMBERS INTO CLOSE RELATION WITH ONE ANOTHER SUBSTANTIALLY THROUGHOUT THEIR LENGTH TO FORM ONE OR MORE COMPOSITE MEMBERS EACH COMPRISCOMPOSITE MEMBERS LONGITUDINALLY TO FORM THE BRADKING-FACE PORTION OF THE STRIP; AND SUBJECTING SAID ARRANGED COMPOSITE MEMBERS TO HEAT AND PRESSURE AND FORMING A UNITARY BRADKE FRICTIONSTRIP HAVING AN ARCUATE BRAKING-FACE PORTION. COMPOSITE MEMBERS LONGITUDINALLY TO FORM THE BRAKING-FACE PORTION OF THE STRIP; AND SUBJECTING SAID ARRANGED COMPOSITE MEMBERS TO HEAT AND PRESSURE AND FORMING A UNITARY BRAKE FRICTIONSTRIP HAVING AN ARCUATE BRAKING-FACE PORTION. 